Current devices that communicate wirelessly using radio frequencies, such as some handheld computing devices, laptop computers, televisions, desktop computers, and set-top boxes, often have very low efficiencies in the 60 GHz band. In many cases the efficiency of current devices operating in this band is as low as ten percent.
Devices that communicate wirelessly typically transmit information using single-carrier modulation or orthogonal frequency division multiplexing (OFDM) modulation. A single-carrier system modulates information onto one carrier using frequency, phase, or amplitude adjustment of the carrier. OFDM modulation is a frequency division multiplexing scheme that extends the concept of single carrier modulation by using multiple, orthogonal subcarriers to carry information. OFDM modulation, unlike single-carrier modulation, permits use of beam forming to overcome channel-path loss common to the 60 GHz band. However, devices that implement OFDM modulation consume more power relative to devices that implement single-carrier modulation.